o Changes from v1
Use find_next(_zero)_bit suggested by jg.kim
When f2fs issues discard command, if segment is contiguous,
let's issue more large segment to gather adjacent segments.
** blktrace **
179,1 0 5859 42.619023770 971 C D 131072 + 2097152 [0]
179,1 0 33665 108.840475468 971 C D 2228224 + 2494464 [0]
179,1 0 33671 109.131616427 971 C D 14909440 + 344064 [0]
179,1 0 33677 109.137100677 971 C D 15261696 + 4096 [0]
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>